This invention relates to an improved electrical connector device of the type used in track lighting systems. The electrical connector is insertable in a continuous slot in the outer wall of an electrical power track. The track carries a plurality of electrical conductors which are engaged by contact members or electrical terminals positioned on the electrical connector. The contact members are biased by a spring force to remain in contact with the electrical conductors. The contact member may be adjusted to a preselected position to make selective contact with an electrical conductor thus accommodating the selection of a distinct electrical circuit to which the circuit element carried by the electrical connector may be connected. By rotation of the housing of the electrical connector after insertion into the slot opening the rail track, a flange member carried by the housing locks into a support channel located on the track.
In track lighting systems, electrical connecting devices having terminals which connect electically to conductors carried by a supporting track is commonly known. Likewise, it is common for the connecting device to be inserted into the track through a longitudinal slot therein and thereafter rotated into a position where the electrical contact members make contact with the conductors located in the track wall. For example, U.S. Pat. No. 4,218,108 issued Aug. 19, 1980, shows a plurality of contact members which engage the electrical conductors carried by the track upon rotation of an adapter mechanism or connecting device inserted into a slot opening in the track. Additionally, the aforementioned patent discloses a plurality of flange like members which bear upon and are supported by axially extending shoulders carried in the track structure. The weight of the adapter and the circuit element are supported not only by the flange like members but also by the connecting terminals which engage the electrical conductors carried in the track wall. Typically, the electrical contact members or terminals are rigidly mounted to the housing of the connecting device to provide the additional structural support necessary to carry the weight of the connecting device and the circuit element attached to it.
One of the problems therefore in the present state of the art is that inherent tolerance variations in the extruded track results in slight misalignments between the location of the electrical conductors in the track wall and the contact members of the connecting device. Because of the rigidity of the electrical contact members, the contact members slip out of contact with the electrical conductors during the rotational engagement of the connecting members with the electrical conductors. Additionally, after the connecting device has been rotated and positioned in the track, the contact members are under stress resulting from the static weight of the connecting device and the circuit element carried by it which introduces a further propensity to slip out of electrical contact.
The rigid mounting of the contact members further causes excessive wear to occur in the contact member itself and the electrical conductors located in the track, thus frequent replacement of both contact members and electrical conductors is necessary.
Another problem exists in the prior art which is illustrated in U.S. Pat. No. 4,218,101. Because the flange members which support the adapter by bearing upon the support shoulders contained in the cavity of the track rail do not afford a positive locking means to retain the adapter within the track, the adapter conection to the track has a degree of inherent instability which further limits the static weight to be suspended from the adapter device.